Although the estimated number of HIV cases in the United States (US) has remained the same over the last decade, there is increasing evidence of an epidemic resurgence. New HIV preventive intervention approaches that target HIV infected individuals are being strongly advocated. The current project outlines a unique, multifaceted, and collaborative approach to evaluating HIV preventive interventions that are expected to have an impact at the population level, such as would be expected from interventions that are implemented with HIV infected individuals. One study provides strong evidence that interventions implemented with HIV infected individuals not only have an impact at the population level, but can be evaluated at that level as well. The current project proposes the development of evaluation tool that relies on establish surveillance methodology and is in preparation for an intervention conducted with HIV infected individuals. The evaluation tool will be used to provide baseline data on population herpes simplex virus-2 (HSV-2)/HIV co-infection, as well as to evaluate a future HIV preventive intervention that provides HSV-2 suppressive therapy to HSV-2/HIV co-infected individuals. To that end, we propose the following specific aims: Aim 1: An evaluation tool or sentinel will be developed to assess HSV-2/HIV co-infection incidence and prevalence and will contain basic demographic information; the validity and feasibility of the evaluation tool will be assessed through a pilot study conducted during the first quarter of data collection. Aim 2: To explore the HIV transmission dynamics associated with HSV-2 co-infection, comparable analyses will be conducted (a) with the evaluation tool data set, (b) with the parent study data set, and (c) comparing the results between the two data sets. Aim 3: The feasibility of transferring and adapting the methodology and technology for ongoing sentinel surveillance in this community as an academic/public health collaborative effort will be assessed. Finally, the methodology developed for this evaluation tool may be adapted for use in the evaluation of social network interventions, community level interventions, and other interventions implemented with individuals expected to have an outcome at the population level. [unreadable] [unreadable]